/* ==========================================
 * JGraphT : a free Java graph-theory library
 * ==========================================
 *
 * Project Info:  http://jgrapht.sourceforge.net/
 * Project Creator:  Barak Naveh (http://sourceforge.net/users/barak_naveh)
 *
 * (C) Copyright 2003-2008, by Barak Naveh and Contributors.
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or
 * (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
 * License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library; if not, write to the Free Software Foundation,
 * Inc.,
 * 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
 */
/* ------------------------------
 * ShortestPathTestCase.java
 * ------------------------------
 * (C) Copyright 2003-2008, by John V. Sichi and Contributors.
 *
 * Original Author:  John V. Sichi
 * Contributor(s):   -
 *
 * $Id: ShortestPathTestCase.java 1258 2013-04-18 20:27:18Z freecode4susant $
 *
 * Changes
 * -------
 * 14-Jan-2006 : Factored out of DijkstraShortestPathTest (JVS);
 *
 */

package org.jgrapht.alg;

import junit.framework.*;

import org.jgrapht.*;
import org.jgrapht.graph.*;

import java.util.*;

/**
 * .
 *
 * @author John V. Sichi
 */
public abstract class ShortestPathTestCase extends TestCase {

    static final String V1 = "v1";
    static final String V2 = "v2";
    static final String V3 = "v3";
    static final String V4 = "v4";
    static final String V5 = "v5";
    DefaultWeightedEdge e12;
    DefaultWeightedEdge e13;
    DefaultWeightedEdge e15;
    DefaultWeightedEdge e24;
    DefaultWeightedEdge e34;
    DefaultWeightedEdge e45;

    /**
     * .
     */
    public void testPathBetween() {

        final Graph<String, DefaultWeightedEdge> g = create();
        List path                                  = findPathBetween(g, V1, V2);

        assertEquals(Arrays.asList(new DefaultEdge[] { e12 }), path);

        path = findPathBetween(g, V1, V4);

        assertEquals(Arrays.asList(new DefaultEdge[] { e12, e24 }), path);

        path = findPathBetween(g, V1, V5);

        assertEquals(Arrays.asList(new DefaultEdge[] { e12, e24, e45 }), path);

        path = findPathBetween(g, V3, V4);

        assertEquals(Arrays.asList(new DefaultEdge[] { e13, e12, e24 }), path);
    }

    protected abstract List findPathBetween(Graph<String, DefaultWeightedEdge> g, String src,
            String dest);

    protected Graph<String, DefaultWeightedEdge> create() {
        return createWithBias(false);
    }

    protected Graph<String, DefaultWeightedEdge> createWithBias(final boolean negate) {

        final Graph<String, DefaultWeightedEdge> g;
        double bias = 1;

        if (negate) {


            // negative-weight edges are being tested, so only a directed graph
            // makes sense
            g    = new SimpleDirectedWeightedGraph<>(DefaultWeightedEdge.class);
            bias = -1;
        } else {


            // by default, use an undirected graph
            g = new SimpleWeightedGraph<>(DefaultWeightedEdge.class);
        }

        g.addVertex(V1);
        g.addVertex(V2);
        g.addVertex(V3);
        g.addVertex(V4);
        g.addVertex(V5);

        e12 = Graphs.addEdge(g, V1, V2, bias * 2);
        e13 = Graphs.addEdge(g, V1, V3, bias * 3);
        e24 = Graphs.addEdge(g, V2, V4, bias * 5);
        e34 = Graphs.addEdge(g, V3, V4, bias * 20);
        e45 = Graphs.addEdge(g, V4, V5, bias * 5);
        e15 = Graphs.addEdge(g, V1, V5, bias * 100);

        return g;
    }
}

// End ShortestPathTestCase.java


